Method of making artificial stone



Oct. 16, 1962 B. M. ROWE METHOD OF MAKING ARTIFICIAL STONE 2 Sheets-Sheet 1 Filed March 16. 1960 INVENTOR. BA RTHOLOMEW M. Rows 0d. 16, 1962 B. M. ROWE 3,058,164

METHOD OF MAKING ARTIFICIAL STONE Filed March 16, 1960 2 Sheets-Sheet 2 F IG. INVENTOR.

BAIZTHOLOMEW M. Rgwc- United States Patent Oflice p 3,058,164 Patented Oct. 16, 1962 3,058,164 METHOD OF MG ARTIFECTAL STONE Bartholomew M. Rowe, Los Angeles, Calif., assignor of twenty-five percent to Charles W. Howard, Sherman Oaks, Calif.

Filed Mar. 16, 1960, Ser. No. 15,411 Claims. (Cl. 18-483) This invention generally relates to a method of forming slabs of molded material, and more particularly relates to a method of forming slabs of concrete with one side thereof textured to simulate natural stone and rock materials.

At the present time, the usefulness of the invention is primarily directed towards providing a simulated stone and rock facing material for the exterior or interior side Walls of residential, commercial, and industrial buildings of various types.

It will be appreciated that natural rock and stone materials in the form desired are not generally available at the usual job site, and oftentimes must be transported great distances at considerable cost in order to be employed in building construction. Also such natural stone and rock materials are relatively expensive and ditficult to procure in particular sizes and configurations that may be needed. On the other hand, it is well-known that a stone or rock facing on a building not only lends an aesthetic appearance to the building, but also decreases maintenance costs involved in painting, sandblasting, and related work associated with conventional exterior building finishes. Although the present invention will be described from the standpoint of its application in producing slabs of concrete material to simulate stone and rock, it will be appreciated that the invention may also be applied to other types of materials which are to be molded to meet analogous requirements.

With the foregoing in mind, an important object of the present invention is to provide an economical and efficient manner of producing slabs of concrete with one side surface thereof being textured to simulate natural stone and rock material.

Another object of the present invention is to provide a method of producing slabs of concrete simulating natural stone and rock formations, in which the coloring matter embodied in the slabs is deposited in such a manner that the slabs very closely approximate the coloring of natural rock and stone material.

Another object of the present invention is to provide a method of forming slabs of concrete material simulating on one side thereof natural rock and stone formations, in which the slabs may be formed for use about corners of buildings and yet which at the same time enables slabs to also be formed in a convenient shape for economical shipment to the job site.

Another object of the present invention is to provide a method of forming slabs of concrete material simulating on one surface thereof natural stone and rock, in which the slabs may be formed without the requirement of any expensive tooling and by employing relatively unskilled personnel.

Still another object is to provide a method of forming slabs of concrete material simulating on one surface thereof natural rock and stone materials, where the total square footage required for the job requirements may be closely approximated.

These and other objects and advantages of the present invention are generally attained by providing a method of making slabs of molded material to have or be characterized by an irregularly contoured and colored surface on one side thereof simulating natural stone and/or rock. The method comprises the steps of first forming a mold for receiving the material with the mold embodying a base member of generally rectangular configuration, and having U-shaped marginal side walls on the material receiving side thereof. The side walls are designed so as to act as a gauge for establishing thickness of the ultimate slab to be formed. Also, the base member is provided with an irregularly contoured surface portion including areas thereof angled with respect to the plane of the base member on the material receiving side.

After the molds have been so formed, coloring matter is deposited on the irregularly contoured surface portions, and the mold is then filled with the liquid concrete aggregate material to the height of the side walls.

After the molded material has hardened or set, a slab will be formed of uniform thickness, according to the height of the side walls, and having an irregularly contoured and colored surface on the side juxtaposed with respect to the irregularly contoured surface of the mold.

Preferably, during the depositing of the coloring matter on the mold, the mold is inclined such that the areas angled with respect to the base member will be substantially horizontal to enable the adhering of the coloring matter as it is deposited onto the irregularly contoured surface portion of the base member in the mold.

Also, it is desirable in accordance with a feature of the present invention that the molds be stacked in longitudinally staggered relationshi whereby corner slabs may alternately be formed, all as will become clearer as the specification proceeds.

A better understanding of the present invention will be had by reference to the drawings, merely schematically indicating for illustrative purposes certain of the features of the steps of the method, and in which:

FIGURE 1 is an isometric view of a mold formed in accordance with the method of the present invention;

FIGURE 2 is a side view of the mold of FIGURE 1 inclined according to the method of the present invention in position for application of coloring matter thereto;

FlGURE 3 is a view of several molds formed according to the present invention as they are stacked in staggering relationship after being filled with a molded material or concrete;

FIGURE 4 is a view of a slab of concrete formed according to the present invention and having one surface or side thereof simulating natural stone or rock, the particular slab of FIGURE 4 being adapted for use about the corner of a building or structure; and

FIGURE 5 is a view of another slab formed according to the method of the present invention, for example, as shown in FIGURE 3, not embodying a corner portion.

Referring now to the drawings, there is shown in FIG- URE 1 a mold employed in conjunction with the method of the present invention. Preferably, the mold embodies a base member 10 of generally rectangular shape. The base member 10 has upstanding therefrom side walls 11, 12, and 13 which are of given height according to the thickness of the slab to be formed. The side walls 11 and 12 extend along the marginal sides of the base mem ber 10, while the sidewall 13 closes off one of the ends thereof.

In one form, the base member 10 may merely comprise a sheet of plywood material, while the sidewalls 11, 12, and 13 may consist of wooden members formed of one inch by two inch stock, two inch by four inch stock, or the like according to the particular thickness of the slab desired. It will be appreciated, however, that the mold may be formed of other materials to the particular rectangular shape as shown.

The base member 1% is provided on the upper surface thereof with a layer of bonded Fiberglas or rubber 14 having an irregularly contoured outer surface portion 15 characterized by ridges, valleys, crevices, indentations,

and the like to simulate the appearance of natural rock and stone contours.

In accordance with the method of the present inven tion, after the mold has been formed in accordance with the shape of FIGURE 1 it is positioned on a floor 16 or other supporting surface and tilted to an angle of approximately 45 degrees preparatory to the depositing of coloring matter thereon. The particular angle to which the mold is tilted may vary to a great degree depending upon the particular coloring effect desired in the concrete slab being formed. Thus, the surface portion of the mold material 14 normally will include various sloped portions 17, 18, and 19, extending between relatively high and low areas of the irregularly contoured surface. By tilting the mold to an angle of approximately 45 degrees, assuming the portions 17, 13, and 19 are nominally of approximately a 45 degree slope, relative to the plane of the base or bottom member 10, these portions will be in a substantially horizontal position such that coloring matter will adhere thereto. Generally speaking, any angle between 30 degrees to 60 degrees is usually satisfactory for this purpose.

Thus in accordance with the method of the present invention, the coloring matter, usually of a powdered form is deposited in the direction of the arrows or vertically downwardly by gravity through manual sifting, spraying or the like from a container to form minute layers of coloring matter at 20, 21, and 22. Thereafter, it is desirable that the coloring matter be moistened prior to filling of the molds.

It will be appreciated that if the mold were not tilted as shown, the coloring matter would all settle to the bottom of the valleys, crevices, or the like, characterizing the irregularly contoured surface portion 15. Thus, by so angulating the mold relative to the horizontal, in accordance with the present inventive method, the coloring matter will adhere to the sloped areas of the contoured surface in order to achieve the desired simulated effect of natural stone or rock in the surface of the slab formed on the mold, as will become clearer as the specification proceeds.

After the coloring matter has been deposited upon the mold, it may again be placed in a horizontal position to be filled with the particular concrete or cement and aggregate mixture employed. This latter step of the method is illustrated by FIGURE 3.

Thus, as shown in FIGURE 3, a mold 23, substantially identical to the mold described in conjunction with FIG- URES 1 and 2, is filled with molding material 24 to the height of the side walls thereof.

In accordance with a feature of the present invention, after the mold 23 has been filled with the material 24, and prior to the time it sets, another mold 25 is placed upon the mold 23 and supported by the sidewalls thereof in a longitudinally staggered position relative to the mold 23. Next, the mold 25 is filled with concrete material 26, and thereafter another mold 27 is placed upon and supported by the side walls of the mold 25, to also be filled with concrete material 23. Thereafter mold 29 is supported from the mold 27, and so on.

For convenience in illustration, the molds 23, 25, 27, and 29 have been shown as including the mold material as an integral part of the base structure, which is also an alternative method of construction of the molds.

Thus, with this type of stacking of the molds in longitudinally staggered relationship, it will be appreciated, for example, that the mold 25 has its open end portion 30 extending a given distance beyond the closed end portion of the lowermost mold 23. As a consequence, the closed end portion 31 of the mold 25 will be disposed above and inwardly of the open end portion of the mold 23.

In view of this inter-relationship of the molds 23 and 25, a corner 32 may be formed from the slab material 24-.

4 Of course, a similar corner may be formed as between the molds 27 and 29 as partially indicated.

In consequence of the method of stacking the molds, as shown in FIGURE 3, in conjunction with the co-operating mold structure as such as shown in FIGURE l, it is possible to form a series of corner slabs (for example, 24) alternating with flat slabs (for example, 26). The finally produced slabs are more clearly shown in the view of FIGURES 4 and 5.

Thus, in FIGURE 4, there is shown a corner slab 24 having a corner portion 32. The slab 24 has an upper surface 33, as viewed in FIGURE 4, which is flush in view of the fact that it has been leveled off by the mold 2S and the closed end thereof. The slab 24 has an irregularly contoured lower surface 33 which is formed with an exterior surface portion of the corner 32, denoted by the numeral 35.

The irregularly contoured surface portion 35 of the corner 32 may be formed manually by hand since it is of relatively small overall dimensions. In this regard, it should be noted that the corner 32 together with the slab corners aligned above it will form a substantially solid wall (except for open end mold edges) whereby manual application of coloring matter and shaping is convenient.

It will be appreciated that in stacking the molds 23, 25, 27, and 29, as shown in FIGURE 3, that the mold 25, in order to maintain the thickness of the slab 24 throughout its corner portion 32, should extend exactly a distance equalling the desired slab thickness beyond the closed end portion of the mold 23. Thus, the open end portion of the mold 25 should be approximately one inch beyond the closed end portion of the mold 23, assuming the height of the side walls of the molds being used are approximately one inch from the base member employed therewith. Of course, if the sidewalls are higher, the open end of the mold 25 will extend out further relative to the closed end of the mold 23 according to the particular given height of the sidewalls and corresponding desired thickness of the slab.

The slab 26 shown in FIGURE 5 is merely illustrative of a conventional slab formed by the mold 25. The particular number of corner slabs (for example, slab 24) to be formed will normally be a percentage of the total slabs being furnished for the particular material job requirements. Of course, this percentage will vary according to the area to be covered relative to the particular corners being enclosed, but usually can be estimated relatively closely by the contractor or architect. Thus, if fewer corner slabs are required than conventional flat slabs, as the molds are stacked one upon the other, certain of the molds may be aligned to produce more flat slabs than corner slabs rather than in the alternating manner suggested by FIGURE 3.

It will be evident in shipping the slabs 24 and 26 that they may be readily nested together for economical and convenient transportation.

On the job site, the slabs will normally be broken apart into various configurations to simulate stones or rocks and then the fiat sides thereof secured in plaster or the like to the building side walls. Desirably one inch thick slabs are formed in order to comply with building requirements for adherent veneer.

It will be appreciated that with the method of the present invention not only is an economical and efiicient means attained of producing concrete slabs having a surface portion thereof simulating natural stone and rock, but also a method has been achieved such that the slabs may be economically and efiiciently formed to be used upon corners of the building and also for the purpose of convenient transportation, shipping, and measurement by square footage to meet job requirements. It will further be appreciated that by providing the unique manner of applying coloring matter, in accordance with the method ,of the present invention, that a more closely simulated natural stone and rock appearance is attained.

Of course, certain variations and modifications in the method of the present invention will occur to those skilled in the art without departing from the spirit and scope of the invention as set forth in the following claims.

What is claimed is:

1. In a method of making a slab of molded material characterized by an irregularly contoured and colored surface on one side thereof the steps of: forming a mold for receiving said material, said mold being formed with a base member and U-shaped marginal side walls on the material receiving side thereof, with said side walls being designed as a gauge for establishing the thickness of said slab, and said base member being formed with an irregularly contoured surface portion bordered by said sidewalls including areas thereof angled With respect to said base member on said material receiving side; inclining said mold such that a part of said angled areas will be substantially horizontal; depositing powdered coloring matter on said irregularly contoured surface portion, while said mold is inclined such that said coloring matter will adhere to said part of said angled areas; positioning said mold in a horizontal plane; and filling said material receiving side with molding material to the height of said sidewalls, whereby a slab is formed having an irregularly contoured and colored surface defined by the contour and coloring matter disposed on the irregularly contoured surface portion of said mold.

2. In a method of making a slab of molded material characterized by an irregularly contoured and colored surface on one side thereof, the steps of: forming a mold to receive said material including a flat base member and upstanding marginal side walls, said base member being irregularly contoured on the material receiving side thereof in the area bordered by said sidewalls; inclining said mold such that said base member is at an angle relative to the horizontal with the material receiving side of said base member being disposed upwardly such that certain areas of said irregularly contoured surface portion will be substantially horizontal; depositing powdered coloring matter by allowing same to fall by gravity on said irregularly contoured surface portion; and, positioning said mold in a horizontal plane for filling with said material for molding.

3. In a method of making a slab of molded material characterized by an irregularly contoured and colored surface portion on one side thereof, the steps of: forming a plurality of rectangular shaped molds to receive said material, each of said molds being provided with upstanding marginal side walls on both side edges and one end thereof on a material receiving side thereof so as to leave the opposite end thereof open, and said material receiving side being irregularly contoured in the area bordered by said sidewalls; depositing coloring matter on said material receiving side of said molds; placing a first one of said molds upon a supporting surface; filling said first one of said molds with said molded material to the height of said side walls to form a first slab; placing a second one of said molds upon said first one of said molds, said second one of said molds benig positioned such that said opposite end thereof is disposed above and projects outwardly a given longitudinal distance beyond the closed end of said first one of said molds whereby the closed end of said second one of said molds is disposed above and inwardly of the open end of said first one of said molds, and whereby said molded material may be extended around said closed end of said second one of said molds to form a corner to said first slab.

4. The subject matter, according to claim 3, and filling said second one of said molds to form a second slab.

5. The subject matter, according to claim 3, and canting said mold to the horizontal while depositing said coloring matter on the material receiving side thereof such that said coloring matter will adhere to the higher points of said irregularly contoured area.

References Cited in the file of this patent UNITED STATES PATENTS 856,519 Decks June 11, 1907 1,168,492 Freund Jan. 18, 1916 1,570,998 Egger Jan. 26, 1926 1,608,281 Weber Nov. 23, 1926 1,681,727 Emerson Aug. 21, 1928 2,144,388 Quasebarth Jan. 17, 1939 2,517,432 Hornberger Aug. 1, 1950 FOREIGN PATENTS 7446/27 Australia May 23, 1927 217,805 Australia Oct. 23, 1958 714,341 Germany Nov. 6, 1941 766,896 Great Britain Jan. 30, 1957 

